Gastroesophageal Reflux Disease (GERD) is a common disorder caused by the reflux of gastric (stomach) acid into the esophagus. The exposure of the lining of the esophagus to the acid will cause damage to the esophagus over time. The symptoms of GERD include heartburn and acid regurgitation This study will determine if Tegaserod alone and in combination with omeprazole is safe and relieves the symptoms of heartburn.

Inclusion Criteria:

• History of physician diagnosed GERD
• Heartburn and Regurgitation 3 Days during the week prior to screening

Exclusion Criteria:

• History of erosive esophagitis, Barrett's esophagus, esophageal stricture, scleroderma, Zollinger-Ellison Syndrome, known primary disorder
• History or presence of infection or inflammation of the small or large intestine, gastrointestinal malignancy, history of upper GI surgery
• Use of PPI during the last four weeks prior to screening

Other protocol-defined inclusion/exclusion criteria may apply.